#!/bin/bash
#普通输出for循环
for i in "12a" "b0" "c24" "d45" "e56"
do
     echo $i
done
# 1-100每个数字的平方数
for i in $(seq 100)
do
  echo "$i ($i*$i) $(($i*$i))"
done


# 1-100每个数字之和
s=0
for ((i=1;i<=100;i++))
do
  s=$(($i+$s))
done
echo $s

#批量添加用户


read -t 30 -p "please enter a file name" file